So in trying to get to know my cast iron skillet, I made cornbread the other day. This to go along the oven-baked ribs. Only my recipe called for a 10" skillet. I didn't read this part and poured my batter into my 12" skillet. I also didn't have 2 cups of cormeal, so I substituted about 1/3 cup of all purpose flour to make up the dry ingredients. Used the baking soda, baking powder. sugar, eggs, salt, buttermilk at the original measurements. (BTW this recipe from Joy of Cooking) Cooked for original 20 minutes and out came slightly thinner, definitely dry cornbread.

So to the engineering (or math part). Going back to the measurements, I figure that to go from a 10" skillet to a 12" skillet, I should increase the amount by 44% assuming I want the equivalent height on the cake with the following math. Going from a radius of 5" to 6", which gives 20% difference in radius. I then squared to 25*pi sq. in versus 36*pi sq. in. area on the bottom. Assume 1.5 in height, the volumes become 37.5*pi in^3 versus 54*pi in^3. So difference in volumes is 16.5*pi in^3, which is 44% difference to 25*pi.

So the upshot is, are my calculations correct? (I am a failed engineer, who had to go to medical school instead ) And will I have to change my baking time to compensate?